Salesforce has a concept called Queues in which work can be organized. Queues are used to hold unassigned records until someone takes ownership of the record. This gives everyone in the Queue an opportunity to see the same records at the same time regardless of their Role in the organization. Once a ticket is assigned to someone (also called taking ownership of a record), then the record can no longer be viewed except by the rules and permissions as set forth in Salesforce.
Queues are managed by Salesforce and as such they are system objects that Salesforce does not necessarily expose via the Salesforce reporting mechanism.
This document will walk you through using the Salesforce Data Loader along with Microsoft Access 2010 to pull the appropriate data and build a report that will show you what queues you have defined and who is a member of those Queues.